1. Field of the Invention
Embodiments of the invention relate to a mask for use in a deposition process, such as a chemical vapor deposition (CVD) process used in the manufacture of electronic devices. In particular, embodiments of the invention relate to a mask utilized in an encapsulation process in the manufacture of organic light emitting diode (OLED) display devices.
2. Description of the Related Art
OLEDs are used in the manufacture of television screens, computer monitors, mobile phones, other hand-held devices, etc. for displaying information. A typical OLED may include layers of organic material situated between two electrodes that are all deposited on a substrate in a manner to form a matrix display panel having individually energizable pixels. The OLED is generally placed between two glass panels, and the edges of the glass panels are sealed to encapsulate the OLED therein.
There are many challenges encountered in the manufacture of such display devices. In some fabrication steps, the OLED material is encapsulated in one or more layers to prevent moisture from damaging the OLED material. During these processes, one or more masks are utilized to shield portions of the substrate that do not include the OLED material. The masks used in these processes must endure significant temperature differences. The temperature extremes cause thermal expansion and contraction of the mask, which may lead to cracks, bending or breakage of the mask, any one of which may cause contamination of portions of the substrate. Additionally, significant electrostatic discharge (ESD) may be present and/or created during these deposition processes. Uncontrolled ESD may damage the OLED material.
Therefore, there is a continuous need for new and improved apparatus and processing methods using masks in forming OLED display devices.